PORTLAND — The father of a Maine toddler whose disappearance generated national attention is back in jail following his arrest for violating his bail conditions, police said.

South Portland police say 26-year-old Justin DiPietro was arrested Friday morning following a traffic stop on Broadway in South Portland.

DiPietro is the father of Ayla Reynolds, who was reported missing from DiPietro’s home in Waterville in December 2011. Ayla, who was 20 months old, is presumed dead and her disappearance remains unsolved.

DiPietro was charged in July with assaulting an ex-girlfriend in Portland and released on bail.

South Portland Police Department Sgt. John Sutton said Officer Scott Corbett pulled DiPietro over around 11 a.m. Friday for driving a vehicle with an expired inspection sticker.

Corbett ran a background check on DiPietro and found that his bail conditions require that he submit to random alcohol and drug tests. He is also not allowed to possess alcohol.

Corbett discovered that DiPietro had alcohol in his vehicle, which constituted a violation of his bail conditions. He was arrested and taken to the Cumberland County Jail where he spent the weekend.

A jail official said DiPietro was returned to jail after making a court appearance Monday, but he didn’t know if he had an attorney.

DiPietro was being held Monday evening at the jail on $210 cash bail.